1. Technical Field
The following description relates to one or more communication techniques for establishing secure communication between a server and a client.
2. Related Art
As a communication technology employed for communication between a plurality of devices on a network, an SSL (Secure Socket Layer) communication technology has been known in which the communication is switched to encrypted communication by transmitting a public key using an electronic certificate. Such encrypted communication is not used even in a communication system configured to perform the encrypted communication unless a user indicates his intention of using the encrypted communication at a computer side. In other words, low security communication might be performed even in the communication system configured to perform the encrypted communication due to an improper communication protocol selected by the user at the computer side.
As a conventional technology to solve the above problem, there has also been known a technology in which a computer connected with two networks of different security levels can switch to connection with a higher-security one of the networks when performing communication of high secrecy information (see Japanese Patent Provisional Publication No. HEI 11-25046).